Circuit Breaker States
A circuit breaker cycles through three states: Closed (requests flow normally), Open (requests are blocked after failures), Half-Open (a few test requests check if the service recovered).
What is Circuit Breaker States?
A circuit breaker cycles through three states: Closed (requests flow normally), Open (requests are blocked after failures), Half-Open (a few test requests check if the service recovered).
Circuit Breaker States is a intermediate-level concept that sits in the Microservices Architecture area of system design. Engineers reach for it whenever they need to reason about real-world trade-offs in that space — not just for textbook correctness, but because real production systems at companies like Netflix, Amazon, and Google make these decisions every day.
If you want to go deeper than this definition — with diagrams, code, and a quiz to lock it in — work through the "Circuit Breaker States" lesson linked below. It walks through the why, the mechanism, the trade-offs, and how the giants actually use it in production.
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Related glossary terms you might want to look up next.
Circuit Breaker
A pattern that stops calling a failing service after repeated failures, preventing cascade failures. Like an electrical circuit breaker that cuts power to prevent fires.
Retry
Automatically re-attempting a failed operation, usually with exponential backoff. Essential for handling transient failures in distributed systems.
Timeout
A maximum duration to wait for an operation to complete before giving up. Without timeouts, a stalled dependency can hang your entire system indefinitely.